[mikemaccana]

Merge after quicknode/solana-program-examples#155. This PR names MINIMUM_SHARES, inflating_shares_through_own_borrow_does_not_pay and sole_supplier_leaves_the_minimum_behind, which exist only on that PR's branch until it merges.

What was untrue

• lending.md, failure modes: "The donation attack fails because available_liquidity, not the vault balance, is the source of truth." The donation does fail, but the sentence implied the reserve was safe from share inflation, and it wasn't. A reserve's size also counts the interest its borrowers owe, and a supplier may borrow from their own reserve.
• The Adversary chapter: listed ignoring donations as the lending market's only defence.
• lending.md, first deposit: "The first deposit into a reserve mints shares one-to-one." After Refine prose for clarity and consistency across chapters #155 it withholds 1,000 shares.
• lending.md, wall-clock leftovers: three statements Reorganize reader guidance by audience and skill level #151 made untrue:
  • "interest that compounds by the slot"
  • "a single slot's interest"
  • "slot-warping" in the testing section

Changes

• Lending and Borrowing:
  • Maria makes each reserve's first deposit, 1,001 minor units, so she holds one share and 1,000 are withheld. That keeps every later number in the chapter and its figures exact.
  • The share formula counts the withheld 1,000.
  • The solvency invariant now says the shares, plus the withheld 1,000, are a claim on total liquidity.
  • The failure mode is rewritten around the borrow route, with the test's numbers: 4,000 → 4,155.20 USDC without the lock; with it, the attacker ends 1,065 minor units down.
  • The three wall-clock statements are corrected.
• The Adversary:
  • The lending reserve is the second example, after perpetual futures, of a recorded pool size that the pool's own users can raise.
  • The summary now says the lending market uses both defences: it ignores donations and it locks shares.
• WRITING-PLAN: Maria's opening deposits, and her three share accounts in the account map, join the list of steps waiting for a figure.

Checks

• Lint: npm run lint is clean.
• Figures: node scripts/check-figure-geometry.mjs is clean across 99 figures.
• Build: npm run build-pdf writes the PDF.
• Identifiers: I searched for every identifier the new prose names; each one is defined on the Refine prose for clarity and consistency across chapters #155 branch.

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https://claude.ai/code/session_013vsKb7K4wGqggas2vtABoF

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